FLAME-RETARDED RESIN COMPOSITION AND INSULATING SUBSTRATE AND PRINTED CIRCUIT BOARD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a flame-retarded epoxy resin composition ensuring high flame retardance without including a halogen and using a slight amount of a flame retardant while suppressing lowering of moldability and mechanical and electric characteristics. SOLUTION: This flame-retarded resin composition is an epoxy resin composition comprising (A) a phenol-novolak epoxy resin in which a phosphorus atom is integrated in a molecular skeleton without including a halogen and (B) dicyandiamide as a hardener. Instead of the dicyandiamide (B), one of (C) a phenol-novolak resin in which a phosphorus atom is integrated in a molecular skeleton, (C) a phenol-novolak resin in which a nitrogen atom is integrated in a molecular skeleton and (E) a phenol-novolak resin in which phosphorus and a nitrogen atoms are integrated in a molecular skeleton may be mixed. The objective insulating substrate is obtained by thermal press-molding a prepreg composed of a sheet-like fibrous base material impregnated with the resin composition and dried.